Travel adjusting device for valve electric actuating mechanism

A travel adjusting device for a valve electric actuating mechanism comprises a central shaft, an upper limit cam, a lower limit cam, a long gear shaft and a short gear shaft. A protruding ring body is disposed in the middle of the central shaft. Two opposite arc-shaped grooves are arranged on the central shaft. One of the arc-shaped grooves is a long groove penetrating axially. The other arc-shaped groove is a short groove from the upper end face of the central shaft to the upper end face of the ring body. The upper limit cam and the lower cam are located above the ring body and below the ring body respectively. The long gear shaft is disposed in the long groove and meshed with internal teeth of the lower limit cam. The short gear shaft is disposed in the short groove and meshed with internal teeth of the upper limit cam. The upper end and the lower end of the central shaft are connected to an upper compressing plate and a lower compressing plate respectively. The lower end of the long gear shaft is inserted